Golf Ball With Dimple-Free Zones

ABSTRACT

A golf ball is disclosed comprising dimple-free zones; such dimple-free zones may be substantially free of surface irregularities, and may be used by a player to align a shot. Unintentional spin and trajectory deviations may be avoided or minimized when a putt or other low-speed shot strikes the golf ball on such a dimple-free zone. In some applications, a plurality of dimple-free zones may be disposed in locations that are distributed symmetrically on a surface of the ball. Methods of manufacturing such a golf ball are also disclosed.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of U.S. provisional patent application Ser. No. 63/154,062, filed Feb. 26, 2021, the disclosure of which is incorporated herein by reference in its entirety.

FIELD OF THE DISCLOSURE

Aspects of the disclosed subject matter relate generally to golf ball manufacture and implementation, and more particularly to a golf ball comprising dimple-free zones that may be disposed in locations that are distributed symmetrically or equidistantly on a surface of the ball.

BACKGROUND

In the early days of golf, pioneering players and equipment innovators discovered that a golf ball would (for reasons that were not fully understood at the time) fly further if the surface had been scratched or roughed up than it otherwise would have if the surface were in smooth and pristine condition. The evolution of modern engineered balls began with acknowledgement of the effects of those unintentional scratches, then advanced to manufacture of deliberately textured patterns, and finally matured into the calculated, much-studied, and computer-modeled dimple patterns that are now common in conventional golf balls. As with many choices for athletic equipment, selection of a golf ball having a particular pattern of dimples is usually a matter of preference for the user, so many manufacturers typically try to produce a range of products having particular embodiments that will be suitable to the broadest possible range of consumers.

In short, in the context of the surface of a golf ball, the term “dimple” generally refers to a depression having raised edges, and the term “pattern” generally refers to the size, shape, configuration, and arrangement of those dimples on the surface of a particularly dimpled ball. In operation, the number, size, shape, contour, and configuration of the dimples on the surface of a golf ball, i.e., the “pattern,” has been established (and is generally understood) to influence the flight trajectory, spin, and controllability of a golf ball that has been struck with a golf club. With respect to optimum or improved patterns for certain situations, numerous dimple sizes, shapes, configurations, arrangements, and modifications, as well as dimple symmetries, contrived asymmetries, and the like have been proposed, studied, tested, and implemented, all with the goal of reducing drag and improving overall flight performance of a golf ball for various playing and atmospheric conditions, player competence levels (and player preference), club head velocity upon contact with the golf ball, and a combination of these and a variety of other factors.

As just one example, European patent publication number EP0234081 B1 describes some purported benefits of having a ball with dimples of varying sizes—it is proposed that each differently sized dimple may improve the performance of a golf ball at a different respective stage of its flight path. For instance, when the diameter of the dimples in a particular pattern is relatively small, the golf ball will fly favorably over a distance immediately after being hit (e.g., until the ball reaches peak flight and starts to fall) but will generally experience diminished distance characteristics (e.g., due to relatively increased drag) as its velocity decreases and it starts to descend. Alternatively, when the diameter of the dimples in a particular pattern is relatively large, the golf ball will generally experience less drag in the latter stages of flight (e.g., after the ball reaches peak flight and starts to fall), but will not be as effective (i.e., it will experience relatively greater drag, and consequently, will not reach similar overall velocity and preferential trajectories as a small-dimpled ball) in the initial stages of takeoff, immediately after having been struck. In the research and development space, much effort has been devoted to developing unique and innovative dimple patterns that are designed to provide for “optimum” flight characteristics of the golf ball in the air, depending upon player skill level and preference.

In that regard, the golf industry as a whole, and golf ball manufacturers, in particular, have mainly focused on dimple patterns that are directed to optimizing the overall performance of a golf ball to increase distance and performance characteristics that affect trajectory while the ball is in flight. To date, the industry and the golf ball manufacturers, collectively, have completely ignored the overall performance of a golf ball while that ball is rolling on the ground (e.g., when and immediately after having been struck by a putter or in connection with other low-speed, low-compression strikes).

Currently, one of the few improvements to a golf ball pertaining to the act of putting involves painting, etching, drawing, or otherwise providing an image of a circumferential (or partially circumferential) line on the ball which is used for aiming—mostly, this is effectuated by the golfer, and not by the manufacturer of the golf ball. When a player reads a putt and decides which direction of travel to impart on the ball during the putt, the player then sets the ball down with the proposed line of the putt aligned with the line or other directional indicator that has been drawn (typically by the player) on the ball. This method still leaves room for error in the event that the putter face strikes the ball on an uneven surface created by the dimples, or does not strike the ball perfectly flush. Specifically, the dimples tend to cause the ball to veer off course based solely upon contact with the putter face—even if the putter face were moving in the correct direction and if the putt stroke were perfectly aligned. In that regard, the dimple pattern, which is intended to provide an advantage while the ball is in flight, may ultimately tend to create a deleterious effect when the ball is closest to the hole, when clean contact by a putter face with a surface of the ball, and a predictable response by the ball, tend to matter most.

Therefore, there is a need for an improved golf ball manufacturing strategy and implementation in accordance with which a golf ball is provided having dimple-free zones that a player may use as an advantage for putting. When a player strikes the ball with a putter face at such a dimple-free zone, no dimples or uneven surfaces are present to deflect the ball unintentionally from its desired trajectory.

SUMMARY OF THE DISCLOSURE

The following presents a simplified summary of the disclosure in order to provide a basic understanding of some aspects of various representative embodiments disclosed herein. This summary is not an extensive overview of the disclosure. It is intended neither to identify key or critical elements of the disclosed representative embodiments nor to delineate the scope of those embodiments. Its sole purpose is to present some concepts of the invention in a simplified form as a prelude to the more detailed description that is presented later.

The present disclosure describes a golf ball comprising substantially dimple-free, or substantially “smooth” or “uniform” zones that have substantially no surface irregularities, such as dimples. In some implementations, a plurality of such dimple-free zones may be positioned or disposed in locations that are distributed symmetrically or equidistantly on a surface of the ball. In accordance with some rules of golf, a ball must be patterned or textured in a uniform or symmetric manner, and so it may be desirable to distribute the disclosed dimple-free zones symmetrically or equidistantly to produce a “regulation” or otherwise compliant ball that satisfies applicable equipment rules. Such symmetry may also help with aerodynamic characteristics that affect flight of the ball during high-speed, high-compressions strikes as set forth below.

In accordance with one aspect of the disclosed subject matter, for instance, a golf ball may generally comprise: a dimple pattern disposed on a surface of the ball; and a first dimple-free zone disposed on the surface, wherein the first dimple-free zone is substantially free of surface irregularities. Implementations are disclosed wherein the first dimple-free zone is circular in shape, wherein the first dimple-free zone is in a shape that is contoured based upon a portion of the dimple pattern that is occupied by the first dimple-free zone, and wherein the first dimple-free zone comprises a circumferential band.

In one aspect, a golf ball may further comprise an additional dimple-free zone disposed on the surface, wherein the additional dimple-free zone is substantially free of surface irregularities and positioned opposite the first dimple-free zone on an axis through the ball.

A golf ball may further comprise a plurality of additional dimple-free zones, wherein each of the plurality of additional dimple-free zones is substantially free of surface irregularities, and wherein the first dimple-free zone and the plurality of additional dimple-free zones are distributed symmetrically or equidistantly on the surface.

Implementations are disclosed in which a golf ball further comprises an additional dimple-free zone disposed on the surface, wherein the additional dimple-free zone is substantially free of surface irregularities and comprises an additional circumferential band, and wherein the first dimple-free zone and the additional dimple-free zone are distributed symmetrically or equidistantly on the surface.

Additionally or alternatively, a golf ball may further comprise a plurality of additional discrete point dimple-free zones disposed on the surface, each of which is substantially free of surface irregularities, and wherein the first dimple-free zone and the plurality of additional discrete point dimple-free zones are distributed symmetrically or equidistantly on the surface.

In some implementations, a golf ball may further comprise a graphic element disposed on the surface and comprising a visual indictor of a location or orientation of the dimple-free zone. Golf balls are disclosed wherein the dimple-free zone provides a visual cue to align the golf ball for play.

A dimple-free zone may be created to have a size of between about 0.00307 square inches and about 0.19635 square inches, or between about 0.00785 square inches and about 0.7854 square inches or more.

In accordance with another aspect of the disclosed subject matter, a method of manufacturing a golf ball having dimple-free zones may generally comprise: creating a dimple pattern on a surface of the ball; and creating a dimple-free zone on a surface of the ball independent of the dimple pattern, wherein the dimple-free zone occupies a portion of the surface of the ball in lieu of the dimple pattern and is substantially free of surface irregularities.

Methods are disclosed wherein the creating a dimple-free zone comprises disposing the dimple-free zone on the surface in a circular shape, wherein the creating a dimple-free zone comprises disposing the dimple-free zone on the surface in a shape that is contoured based upon a portion of the dimple pattern that is occupied by the first dimple-free zone, and wherein the creating a dimple-free zone comprises disposing the dimple-free zone on the surface in a circumferential band.

In some implementations a method may further comprise: creating a plurality of additional dimple-free zones, each of the plurality of additional dimple-free zones being substantially free of surface irregularities; and distributing the first dimple-free zone and the plurality of additional dimple-free zones symmetrically or equidistantly on the surface.

It is noted that the creating a dimple-free zone may generally comprise occupying an area on the surface having a size of between about 0.00307 square inches and about 0.19635 square inches, or between about 0.00785 square inches and about 0.7854 square inches or more.

The foregoing and other aspects of various disclosed embodiments will be apparent through examination of the following detailed description thereof in conjunction with the accompanying drawing figures, in which like reference numerals are used to represent like components throughout, unless otherwise noted.

DESCRIPTION OF THE DRAWING FIGURES

FIG. 1 is a top view of a putter face striking a conventional golf ball in one manner as is generally known in the art;

FIG. 2 is a top view of a putter face striking a conventional golf ball in another manner as is generally known in the art;

FIG. 3 is a top view of a putter face imparting a spin on a conventional golf ball having been struck in a manner as is generally known in the art;

FIG. 4 is a top view of a putter face imparting a spin on, and affecting a trajectory of, a conventional golf ball having been struck in a manner as is generally known in the art;

FIG. 5 is a top view of a putter face imparting a spin on, and affecting a trajectory of, a conventional golf ball having been struck by a putter face in an “inside out” path as is generally known in the art;

FIGS. 6A through 6C are front perspective views of a golf ball having dimple-free zones in accordance with some aspects of the disclosed subject matter;

FIGS. 7A through 7C are front views of a golf ball having dimple-free zones in accordance with some aspects of the disclosed subject matter;

FIGS. 8A and 8B are front perspective views of a golf ball having dimple-free zones in accordance with some aspects of the disclosed subject matter; and

FIG. 9 is a simplified flow diagram illustrating aspects of one implementation of a method of manufacturing a golf ball having dimple-free zones.

DETAILED DESCRIPTION

Certain aspects and features of the disclosed subject matter may be further understood with reference to the following description and the appended drawing figures. In operation, a golf ball having dimple-free zones may roll truer when struck by a putter face than a conventional dimpled golf ball. In particular, a golf ball as set forth herein may present a substantially smooth (i.e., “dimple-free”) surface area that provides a more predictable and controllable interaction with a putter face (or the face of a short iron) than a conventional dimpled ball, resulting in a more predictable and controllable trajectory being imparted with respect to a path of the ball upon contact.

As noted above, most conventional approaches to golf ball design and development have exclusively sought to address the goal of improving or optimizing surface texture (i.e., the dimple pattern) considerations in such a manner as to maximize or otherwise to optimize aerodynamics across a range of flight regimes, from club head impact to landing—the purpose generally being to deliver a longer, straighter flying golf ball as compared to earlier generations or previous designs.

By way of additional background, and as will be appreciated by those of skill in the art, many slow-motion cameras have captured images of a golf ball being compressed to an oblong shape as it is struck by a driver (or other club) head that may be traveling at more than one hundred miles per hour (100 mph) at impact—this oblong shape may be largely or substantially flat at the point of contact with a club face. As the surface of the ball is flattened (due, for instance, to compression characteristics of the structure of the ball), the number of dimples, and the uniformity of the surfaces of those dimples, that are in contact with the club face upon impact increases. This compression (i.e., flattening of the surface of the ball upon violent, high-speed impact) presents the clubface with a relatively more uniform surface contact area with respect to the golf ball than is generally achievable with low-speed contact that does not cause such deformity or flattening due to compression, such as during a putting stroke. During this compression period, the many dimples that are in contact with the club face work or cooperate in unison such that the texture or non-uniformities of the overall surface of the ball that is in contact with the club face will have little or no effect on the trajectory or overall direction of the ball. Any directional change that is imparted to the ball velocity vector that may even nominally be attributed to the dimple pattern will only generally be realized once the ball has begun its flight and the aerodynamic influences attributable to the (now uncompressed) dimples become greater than the inertial influences attributable to the original force delivered to the ball by the fast-moving club face.

As many enthusiasts are aware, however, there is another element to the game of golf which is just as important as driving and fairway shots; that element is putting (the relatively low-speed, short distance striking of a ball that is never intended to cause the ball to leave the ground, and which implicates none of the aerodynamic considerations of conventional golf ball dimple pattern designs). Unfortunately, putting has largely been ignored by golf ball manufacturers and golf equipment innovators in connection with the development of golf balls since, as noted above, the industry and traditional development efforts have all focused on providing aerodynamic improvements to increase distance, not on controllability in connection with low-speed impacts associated with putting strokes. In the context of the present disclosure, the terms “putt,” “putting,” and similar terms are also intended to encompass chips or other short game plays that, while not necessarily played with a “putter” club, are low-speed enough that they do not compress a ball sufficiently to eliminate or otherwise to reduce the effects of striking a ball on an edge of a dimple as set forth herein.

The act of putting (or chipping) requires finesse, accuracy, “feel” (or instinct), and the ability reliably and repeatedly to impart a desired trajectory (or “line”) to a ball under conditions that do not compress the ball as is common with other golf shots. Many tournaments have been won, or lost, based upon a player making or missing a short putt. Since players must use the same ball throughout a particular hole in accordance with most standard rules of golf, a player generally has no choice but to use the same dimpled ball to putt (on the green) as was used to get from the tee to the green, even though that same dimpled ball was, by design, most likely deliberately and uniquely optimized for distance and flight characteristics (from tee to green) rather than for controllability during putting strokes.

With that background in mind, and turning now to the drawing figures, it is noted that FIG. 1 is a top view of a putter face striking a conventional golf ball in one manner as is generally known in the art, FIG. 2 is a top view of a putter face striking a conventional golf ball in another manner as is generally known in the art, FIG. 3 is a top view of a putter face imparting a spin on a conventional golf ball having been struck in a manner as is generally known in the art, FIG. 4 is a top view of a putter face imparting a spin on, and affecting a trajectory of, a conventional golf ball having been struck in a manner as is generally known in the art, and FIG. 5 is a top view of a putter face imparting a spin on, and affecting a trajectory of, a conventional golf ball having been struck by a putter face in an “inside out” path as is generally known in the art.

It is noted that FIGS. 1 through 5 illustrate well-known, though generally unarticulated, deficiencies in the state of the art of conventional golf ball 100 design and manufacturing methodologies. In particular, FIGS. 1 through 5 illustrate some regimes in which a conventional (i.e., prior art) dimpled golf ball (reference numeral 100) interacts with a contact face 199 of a putter head 190. Specifically, as illustrated in FIGS. 1 through 5, conventional golf ball 100 is depicted (from the top, looking down, as from a golfer's perspective) making contact with contact face 199 of putter head 190. Dimples on a surface of conventional golf ball 100 are indicated by respective depressions 101 and by respective relatively raised portions 102 (it will be appreciated that the dimples themselves are not indicated by separate reference numerals for clarity). Those of skill in the art will appreciate that relatively raised portions 102, when taken together (to the extent that they are raised relative to depressions 101), may also be considered the outer circumferential surface of conventional golf ball 100. Further, while only three dimples are illustrated in FIGS. 1-5 for clarity, it will be appreciated that the entire surface of conventional golf ball 100 is generally dimpled.

It is noted that, when a putt is hit (i.e., at the instant of contact between contact face 199 of putter head 190 and a surface of conventional golf ball 100) at a relatively slow speed, little or no dimple compression on a surface of conventional golf ball 100 takes place. Since there is no compression upon impact, conventional golf ball 100 has a specific point of contact that interacts with contact face 199 (e.g., at an equator of conventional golf ball 100, if it is assumed that contact face 199 is perfectly vertically and horizontally aligned upon impact). Since dimples cover the entirety of the surface of conventional golf ball 100, it is inevitable that contact face 199 of putter head 190 will interact with some portion of a dimple (reference numerals 101 and 102) in a non-uniform manner. In particular, if there is little or no compression imparted to a dimple of conventional golf ball 100, there are several possible scenarios that may occur when contact face 199 of putter head 190 strikes conventional golf ball 100.

First, conventional golf ball 100 may generally travel straight with respect to the intended line of the putt (i.e., in the same direction as putter head 190 is traveling, as indicated by the arrow in FIG. 1) if contact face 199 of putter head 190 strikes a dimple simultaneously on all relatively raised portions 102 surrounding a specific depression 101. This situation is depicted in FIG. 1. Second, conventional golf ball 100 may generally travel straight with respect to the intended line of the putt (i.e., in the same direction as putter head 190 is traveling, as indicated by the arrow in FIG. 2) if contact face 199 of putter head 190 strikes a dimple exactly on an area that separates one dimple from the next (i.e., at a relatively raised portion 102, and only at a relatively raised portion 102). This situation is depicted in FIG. 2. Otherwise, conventional golf ball 100 will most likely veer off in an unintended direction as set forth below.

In particular, it is noted that the illustrations of putter head 190 and conventional golf ball 100 are simplified and stylized in FIGS. 1 and 2, and that these structures are actually three-dimensional, making the contact between them much more complicated than can be shown in the drawings. The idealized interactions between contact face 199 and a surface of conventional golf ball 100 as illustrated in FIGS. 1 and 2 are unlikely, at least because the structures are more intricate than the drawings can depict. More often than not, the contact between putter head 190 and a surface of conventional golf ball 100 will result in one of the outcomes illustrated, by way of example, in FIGS. 3 through 5.

If, for example, contact face 199 of putter head 190 strikes a dimple on one edge or side (i.e., raised portion 102) but fails to hit the other edge or side of the dimple (e.g., an opposed or opposite raised portion 102) because conventional golf ball 100 does not compress during a low-speed putting stroke, then conventional golf ball 100 will tend to oscillate in such a manner as to impart spin, to affect a trajectory, or both. These situations are illustrated in FIGS. 3 and 4, which respectively show spin, on the one hand, and spin in additional to trajectory deviation, on the other hand. The extent to which spin and trajectory may influence a path of conventional golf ball 100 upon being struck by a putter may depend upon a variety of factors, one of which may be defined as the angle by which contact face 199 deviates from flush (or “square”) to the circumferential face of conventional golf ball 100 at impact (referred to below as an “offset angle”). In this context, the terms “flush” and “square” generally refer to a state in which a plane of contact face 199 of putter head 190 is substantially normal to the direction of travel of putter head (as indicated by the arrows in FIGS. 1 through 4) upon contact with conventional golf ball 100.

In FIGS. 3 and 4, the offset angle is illustrated at reference numeral 399 by way of example only. An offset angle 399 of 6 degrees (as compared to a flush or square state) is shown as an approximation only, and only for explanation purposes. Dimple diameter, pattern, and other structural characteristics of conventional golf ball 100, as well as the path and angle of putter head 190, may vary greatly, and therefore the degree to which offset angle 399 deviates from square may also vary.

In that regard, FIG. 5 illustrates a situation in which an angle of contact face 199 is not substantially normal to a path of putter head 190. As many golfers will appreciate, the circumstances illustrated in FIG. 5 may result from putter head 190 being misaligned during a putting stroke, the putting stroke not being linear (or being linear, but not approaching a surface of conventional golf ball 100 such that contact face 199 is normal to a desired trajectory of the putt), or a combination of these and other factors. In that regard, FIG. 5 shows a top view of what golfers refer to as an “inside out” putting stroke, for right-handed golfers; for left-handed golfers, the FIG. 5 situation would represent an “outside in” putting stroke. If contact face 199 of putter head 190 strikes conventional golf ball 100 while also moving on an “outside in,” or an “inside out,” trajectory, the act of catching an edge of a dimple (e.g., raised portion 102) may tend to act as a gear tooth, exacerbating any offset angle 399 and increasing the amount of spin imparted to conventional golf ball 100. As with the discussion above with reference to FIGS. 3 and 4, an offset angle 399 of 10 degrees (as compared to a flush or square state) is shown in FIG. 5 as an approximation only, and only for explanation purposes. Dimple diameter, pattern, and other structural characteristics of conventional golf ball 100, as well as the inside out/outside in path and angle of putter head 190, may vary greatly, making it even more difficult to predict the final trajectory of a putt.

In a departure from conventional technologies, and in an effort to alleviate or otherwise to minimize some of the shortcomings associated with striking a conventional golf ball (such as conventional golf ball 100) with a putter, an innovative golf ball comprising dimple-free zones being substantially free of surface irregularities is disclosed as set forth below.

Specifically, FIGS. 6A through 6C are front perspective views of a golf ball having dimple-free zones in accordance with some aspects of the disclosed subject matter, FIGS. 7A through 7C are front views of a golf ball having dimple-free zones in accordance with some aspects of the disclosed subject matter, and FIGS. 8A and 8B are front perspective views of a golf ball having dimple-free zones in accordance with some aspects of the disclosed subject matter.

As indicated in the various views of FIGS. 6, 7, and 8, aspects of the disclosed subject matter generally relate to a golf ball (reference numeral 600) having dimples but that also incorporates sections or portions with no dimples (what are referred to herein as “dimple-free zones,” illustrated at reference numeral 699). In accordance with one implementation, dimple-free zones 699 may be disposed at opposing ends of each axis in a three-dimensional coordinate system (e.g., X, Y, Z axes illustrated in FIG. 8A) superimposed on ball 600. One purpose of dimple-free zones 699 is to provide a smooth, uniform surface (e.g., at opposing ends of one or more of axes, X, Y, Z) that may be used for contact with a putter (such as contact face 199 of putter head 190). In some implementations, the purpose of locating dimple-free zones 699 as illustrated in the drawing figures is to maintain symmetry of the dimple pattern on ball 600—both for aerodynamic characteristics as ball 600 is in flight, as well as for compliance with rules (such as those promulgated by the United States Golf Association (USGA) and other governing bodies and regulatory agencies, for example) governing golf ball design and construction.

It is noted that the number, physical arrangement or orientation, sizes, and shapes of dimple-free zones 699 are illustrated in the drawing figures by way of example only, and not by way of limitation. For instance, dimple-free zone 699 may be circular in shape (FIG. 7A), or it may be contoured based upon a portion of the dimple pattern that is occupied by dimple-free zone 699 (FIG. 6A) which may, in turn, be affected by the number, shape, size, and uniformity of the dimples employed in the dimple pattern and the size and location of dimple-free zone 699 used in lieu of that pattern; in some implementations, dimple-free zone 699 may comprise a circumferential band that circumnavigates (or at least partially so) ball 600 (FIG. 8A). In some instances, the implementations illustrated in FIGS. 6 and 7 may be referred to as “discrete point dimple-free zones” as a way to distinguish them from the bands or stripes illustrated in FIG. 8, but it will be readily apparent that a discrete point dimple-free zone 699 may be large, while a stripe or band implementation of dimple-free zone 699 may not necessarily extend all the way around a circumference of ball 600.

As another example, ball 600 may have only one or two dimple-free zones 699, though it is noted that in an implementation using only two dimple-free zones 699, it may be desirable that they be disposed at opposite ends of an axis (such as X, Y, or Z, for instance), at least for the reasons mentioned above. The same may be true for implementations using three, four, or more dimple-free zones 699—it may be desirable to position those dimple-free zones 699 symmetrically or equidistantly in locations on a surface of ball 600. Additionally or alternatively, a shape of a dimple-free zone 699 may vary as a function of overall dimple pattern, for instance, or otherwise as desired or necessary to accommodate a putting surface of predetermined area without creating deleterious or otherwise undesirable flight characteristics.

For instance, an area occupied by a dimple-free zone 699 may be as small as an area of one dimple, or only a few dimples (depending upon a size, or a mean or average size, of a dimple in a particular pattern), or it may be as large as 5% or 10% (or more) of an area of an equatorial cross-section of ball 600. In the case of a single dimple, for instance, an area of dimple-free zone 699 may be as small as a circle having a diameter of about 0.0625 inches (i.e., about 0.00307 square inches) or about 0.1 inches (i.e., about 0.00785 square inches), or in the case of a larger area, an area of dimple-free zone 699 may be as large as a circle having a diameter of about 0.5 inches (i.e., about 0.19635 square inches) or about 1.0 inches (i.e., about 0.7854 square inches). Other shapes are possible, and virtually any area of dimple-free zone 699 may be implemented as a design choice or to satisfy industry or USGA standards as set forth in detail below.

As noted above, dimple-free zone 699 may be implemented as a circle (FIG. 7A), a contoured shape (FIG. 6A), a stripe or circumferential band (FIGS. 8A and 8B), or other shape (e.g., squares, triangles, X or cross shapes, and the like), depending upon design choice and playability determinations made or analyzed with respect to ball 600. As is evident from the illustrations in FIGS. 6A, 7A, and 8A, a person of skill in the art will appreciate that the present disclosure is not intended to be limited by any particular size, shape, orientation, or number of dimple-free zones 699 in a particular implementation, and that these may be selected in accordance with desired or required flight characteristics, symmetry for rules compliance, structural stiffness (or pliancy) of an internal structure of ball 600, cost of manufacture, user preference, or a combination of these and a variety of other factors.

In operation, the illustrated implementations may allow a putter face (such as contact face 199) to strike an area (i.e., dimple-free zone 699) that is smooth or that has a consistently textured surface (e.g., a state referred to herein as substantially free of surface irregularities), as opposed to an area with dimples that can affect the trajectory of a putt. As set forth in detail above, a dimple may impart unwanted spin or cause the direction of a ball (when struck by a putter) to deviate from an intended direction—an effect which may be eliminated or minimized in instances where a contact face 199 of a putter strikes a dimple-free zone 699 as illustrated and described.

In some implementations, it may be desirable to construct one or all of dimple-free zones 699 to be visually obvious, such that a golfer using ball 600 may be enabled to align a specific dimple-free zone 699 to an intended putting line. In that regard, dimple-free zones 699 may incorporate, comprise, or be implemented in conjunction with dots, spots, or other point markers or indicia (reference numeral 610 in FIGS. 6B and C and 7C) operative to make dimple-free zones 699 readily apparent (visually) to a golfer, directional lines such as those that describe or indicate a great circle on the surface of ball 600 (reference numeral 620 in FIGS. 6C and 7B and C) and are operative to help with alignment relative to a desired direction of roll (which may define a path of a putt), or both (FIGS. 6C and 7C).

As used herein, each of indicia 610 and directional lines 620 is generically referred to individually as a “graphic element 610, 620,” and collectively as “graphic elements 610, 620”), and is illustrated (in several implementations) in the drawing figures by way of example only and not by way of limitation. Specifically, one or more dimple-free zones 699 may comprise, be adorned with, or have a particular orientation with respect to, a graphic element 610, 620, which may assist a golfer to define and align (both vertically and in a direction of an intended line of travel for ball 600) a specific location of each dimple-free zone 699 when ball 600 is set on a putting surface and positioned for play. Graphic elements 610, 620 may be embodied in or comprise dots, shapes, lines, symbols, alpha-numeric characters, images, or other indicia that are designed and operative to call attention to or otherwise highlight a location of dimple-free zones 699 or great circles on a surface of ball 600 to assist in alignment or directional orientation in putting or other low speed strokes. The present disclosure is not intended to be limited by any particular implementation (in terms of size, shape, nature, color, or other visual characteristic) of graphic elements 610, 620.

As noted above, a diameter or size of dimple-free zone 699 may vary in accordance with several factors, but in practice, it is desirable that dimple-free zone 699 is large enough for a putter face (such as contact face 199) to strike ball 600 at a uniform surface (i.e., a smooth surface which is substantially free of dimples or other surface irregularities), even if ball 600 is not perfectly aligned or the putting stroke is not perfectly square.

As noted above, a surface area of a dimple-free zone 699 may be selected or predetermined as desired, as a design choice or as a function of desired operational characteristics of ball 600, such as flight performance, compression response, spin maximization, or a combination of these and a variety of other factors. In some implementations such as illustrated in FIGS. 6A through 6C and 7A through 7C, a surface area of a dimple-free zone 699 may range in size from as small as a surface area (or a mean or average surface area) of a single dimple to as large as half an inch (½″) or more in diameter (e.g., between about 0.00307 square inches and about 0.19635 square inches or more in area for a single dimple-free zone 699). In other implementations, a surface area of a dimple-free zone 699 may range in size from as small as a surface area (or a mean or average surface area) of a larger dimple (having a diameter of about a tenth of an inch (0.1″), for example) to as large as an inch (1″) or more in diameter (e.g., between about 0.00785 square inches and about 0.7854 square inches or more in area for a single dimple-free zone 699). It will be appreciated that the “diameters” noted above are approximations only, and that a dimple-free zone 699 may not be circular in shape, such that the term “diameter” may not strictly be applicable.

Also as noted above and as illustrated in FIGS. 8A and 8B, a dimple-free zone 699 may also be embodied in or comprise stripes, circumferential swaths, or great circles having no dimples. In these situations, a particular stripe or swath may be as narrow as a single dimple diameter (e.g., between about 0.0625 inches and about 0.1 inches), or may be as wide as five or more dimple diameters (or average or mean dimple diameters), depending upon the dimple pattern of ball 600. In either event, computation of a surface area of dimple-free zones 699 may depend upon the number of stripes or swaths implemented, and how wide those swaths are.

In some alternative implementations, the circumferential swaths of dimple-free zones 699 illustrated in FIGS. 8A and 8B may be manufactured to have dimples, and the areas illustrated in these figures as having a dimple pattern may be embodied in or comprise dimple-free zones. Specifically, those of skill in the art will appreciate that areas having a dimple pattern and the areas represented as dimple-free zones 699 in FIGS. 8A and 8B may be reversed, such that dimple-free zones may predominate a surface area of ball 600, whereas areas comprising a dimple pattern may be limited to circumferential swaths or great circles of one dimple (or a few dimples') diameter in width.

Additionally or alternatively, dimple-free zones 699 may be implemented in any of various combinations of stripes, such as in FIGS. 8A and 8B, and “discrete point” zones, such as in FIGS. 6A through 6C and FIGS. 7A through 7C. In situations where multiple circumferential stripes are employed (as in FIGS. 8A and 8B), those stripes may meet at intersections, reference numeral 830, which may be used by a player for alignment purposes when placing ball 600 in position for play (either on a tee for driving or on a green for putting). In that regard, the implementation in FIG. 8B is illustrated as comprising a graphic element 820 which may facilitate alignment via a visual indicator substantially as set forth above. For purposes of this description, graphic element 820 may be one implementation of a graphic element 620 such as a directional line or other indicator that describes or suggests a great circle or equator of ball 600, though other options are also contemplated.

It is noted that, in any of the various implementations illustrated, contemplated, or readily inferred, one aspect of providing a dimple-free zone 699 is to present a smooth, uniform surface on ball 600 (that is substantially free of surface irregularities and) at which a contact surface 199 of putter head 190 may strike ball 600 such that unintentional torque, spin, or directional bias is not applied to ball 600 (or at least is not exacerbated) upon contact.

In some implementations (such as illustrated in FIGS. 6A through 6C and 7A through 7C), providing areas having no dimples (dimple-free zones 699) at opposing ends of each axis (X, Y, and Z, as illustrated in FIG. 8A), may stabilize ball 600 in the air, and may actually improve overall aerodynamic performance of ball 600 in flight—as compared to a conventional golf ball 100 having a dimple pattern that covers an entirety of its surface. In this situation, a player using ball 600 may experience improved equipment-related performance in shots spanning two different playing regimes, specifically: shots that compress ball 600 (such as drives and fairway play); and shots, such as putts or short chips, that do not.

To summarize the foregoing, the following description provides some examples or use cases (by way of example only) of how dimple-free zones 699 may be implemented on or integrated with a structure of ball 600.

Those of skill in the art will appreciate that, in many implementations, a size or surface area of a dimple-free zone 699, and the manner in which multiple dimple-free zones 699 are disposed, located, or oriented with respect to each other on ball 600 may be important (either to a manufacturer, a player, or both) to the extent that such factors may influence overall performance of ball 600 in various regimes of play. In some situations, for example, where a dimple-free zone 699 has a size or surface area of a single dimple or only a few dimples, the resulting dimensions of dimple-free zone 699 may not be adequate, sufficiently visible, or practically targetable to allow a player to identify the extent of dimple-free zone 699, to align ball 600 for a shot, and subsequently to strike ball 600 at an identified dimple-free zone 699 during a putting or chipping stroke. In accordance with an aspect of the disclosed subject matter, therefore, a golf ball 600 may be constructed in such a manner as to size, dimension, and orient one or a plurality of dimple-free zones 699 to facilitate those objectives, specifically: (i) to allow a player to identify (visually) the location, size, and extent of one or more dimple-free zones 699; (ii) to allow a player visually to align ball 600 for a shot (e.g., a low-velocity shot that does not compress ball 600) based upon the location, size, and extent of such dimple-free zones 699; and (iii) subsequently to facilitate a player striking ball 600 at an identified dimple-free zone 699 during a putting stroke.

In use of some implementations of ball 600, it may be readily apparent that one dimple-free zone 699 may be oriented vertically (i.e., plumb), and another dimple-free zone 699 may be aligned directly to a target line (i.e., in a desired direction of travel for ball 600). This aiming paradigm is illustrated throughout FIGS. 6 through 8, but may be best understood from examination of FIGS. 7A through 7C; in operation, dimple-free zones 699 may provide a golfer with a similar alignment benefit as drawing a line on conventional golf ball 100, and provide the added benefit of allowing contact face 199 to strike a point on ball 600 that does not have (or is at least substantially free of) dimples or other surface irregularities. The area occupied by dimple free zones 699 or intersections 830 may be sufficiently sized and dimensioned to be forgiving, such that, even if ball 600 is positioned offline or a putting stroke is not square, contact face 199 of putter head 190 will nevertheless still strike a dimple-free zone 699.

To summarize:

If a player elects not to use dimple-free zones 699 for advantageous alignment and clean striking characteristics as set forth herein, then ball 600 may still be used in ordinary play as a conventional golf ball 100 (i.e., ball 600 may be constructed in accordance with all applicable USGA rules, or with rules of any other governing body defining acceptable parameters of a playable ball).

FIGS. 6A through 6C and 7A through 7C illustrate ball 600 with areas at the ends of coordinate axes (such as X, Y, and Z shown in FIG. 8A) that have no dimples—i.e., discrete point dimple-free zones 699.

FIGS. 6B, 6C, 7B, 7C, and 8B illustrate dimple-free zones 699 highlighted by a graphic element 610, 620, and 820, intended to call attention to a location or orientation (or both) of dimple-free zones 699. In that regard, graphic elements 610, 620, and 820 may be designed and operative as visual indicators to establish positioning of dimple-free zones 699 and directionality of ball 600 when placed on a putting surface (or a tee) for play.

FIGS. 6C, 7B, 7C, and 8B illustrate dimple-free zones 699 highlighted by a graphic element 620 and 820 comprising a directional line or other indicum to assist with alignment of ball 600 prior to play.

FIGS. 8A and 8B illustrate ball 600 in which dimple-free zones 699 are implemented as bands, swaths, or great circles (or partial circumferential regions) having no dimples. Such bands may circumnavigate ball 600 on one or more than one axis; where more than one axis is so treated, dimple-free zones 699 may be equally spread (i.e., equidistantly) around ball 600 or otherwise in a symmetric manner, may cross each other at intersections 830, and may be so configured and implemented as not to alter applicable flight performance of ball 600 when struck by clubs other than putters or short chipping clubs. In operation, the dimple-free zones 699 illustrated in FIGS. 8A and 8B may be dimple-free or slightly textured; as noted above, they may include or comprise a graphic element 820 that may visually assist with alignment of a putt or other short shot that does not compress ball 600.

It will be appreciated that implementing dimple-free zones 699 as bands, such as in FIGS. 8A and 8B, may also offer additional benefits, such as facilitating a straighter roll as compared to a conventional golf ball 100 with dimples or a ball 600 constructed with discrete point dimple-free zones 699 (see FIGS. 6A and 7A) or other discontinuous regions that are dimple-free.

As noted above, dimple-free zones 699 may be discrete spots, may be circumferential or partially circumferential bands, may be continuous, or may be broken into sections or otherwise non-uniform. Those of skill in the art will appreciate that any of various shapes, sizes, and configurations of dimple-free zones 699 other than those illustrated in the drawing figures are contemplated, and that the present disclosure is not intended to be limited by the examples provided. As set forth herein, some aspects of integrating dimple-free zones 699 into a surface of ball 600 are intended to provide a uniform area (i.e., substantially free of dimples or other surface irregularities) for a contact face of a putter head to strike ball 600, and to distribute such uniform (dimple-free) areas symmetrically or equidistantly around a surface of ball 600, so as not to alter the balance or aerodynamic characteristics of ball 600 in flight.

It is worth noting again that a wide variety of graphic elements (610, 620, and 820), including but not limited to bands or line treatments (such as 620 and 820), may be applied to the design or surface presentation of ball 600. Also, it is noted that a number (and size) of dimples on a golf ball designed and constructed in accordance with traditional methodologies may vary greatly. Some conventional golf balls 100 may be configured with as few as 300 (relatively large) dimples, while others may have as many as 500 or more (relatively smaller) dimples. Irrespective of the number, size, and pattern of dimples used for ball 600 as may be determined as a design choice, it is the overall area comprising dimple-free zones 699 that differentiates ball 600 from a conventional golf ball 100 describe above with reference to FIGS. 1 through 5.

While the present disclosure is not intended to be limited by any particular method, technique, or other industrial process or procedure used to create a shell, coating, cover, or outer surface for ball 600, it is noted that any of various technologies (such as injection molding, stamping, or casting) that are generally known in the industrial manufacturing arts may be used to create the outer surface of ball 600 having integrated dimple-free zones 699.

In that regard, the disclosed subject matter is intended to work in cooperation, or otherwise to be integrated, with golf ball manufacturing techniques and methodologies that are generally known, or that are developed in accordance with known principals, such that dimple-free zones 699 may be created on a surface of ball 600 during ordinary, conventional, or traditional manufacturing processes and process steps.

Returning to FIGS. 1 through 5, conventional golf ball 100 is characterized by a pattern of dimples which covers the entirety of its surface; as noted above and as is generally known, each dimple comprises a depression 101 and relatively raised portions 102 surrounding (and defining) that depression 101. In accordance with one aspect of the disclosed subject matter, a surface of ball 600 also includes a pattern of dimples that is typical or traditional, though the surface of ball 600 is constructed such that it additionally comprises dimple-free zones 699 which do not specifically include depressions 101, relatively raised portions 102, or other surface irregularities or discontinuities.

In that regard, construction of a dimple-free zone 699 may involve providing a surface that is at a level (i.e., a radial distance from a center of gravity of ball 600) that is substantially consistent with that of depressions 101 or of relatively raised portions 102, or neither (e.g., a level that is either lower than depression 101 or higher than relatively raised portion 102, or somewhere in between, may be suitable or desirable in some implementations). In practical applications, it may be desirable to implement dimple-free zones 699 in such a manner as not to alter an average diameter of ball 600 in any material way that affects flight or rolling characteristics. The goal is not to alter the generally spherical shape or contours of ball 600, but rather to respect that generally spherical shape while providing portions of a surface area (i.e., dimple-free zones 699) that are substantially uniform in texture and free from material surface irregularities such as dimples that are engineered for aerodynamic purposes.

In that regard, it is noted that FIG. 9 is a simplified flow diagram illustrating aspects of one implementation of a method of manufacturing a golf ball having dimple-free zones.

As indicated at block 901, a method (identified by reference numeral 900) of manufacturing a golf ball having dimple-free zones may generally begin with providing a golf ball (such as ball 600) that is at least partially manufactured in accordance with traditional manufacturing methodologies. In the context of FIG. 9 and as set forth herein, the phrase “in accordance with traditional manufacturing methodologies” generally refers to, among other method operations, providing a hard rubber (or other generally inelastic) core, spinning rigid or elastic (or a combination of both) fibers around such a core, wrapping one or more intermediate layers of other materials around such a fiber layer, providing a shell or other hardened or hardenable coating or outer layer (e.g., playing surface) on the one or more intermediate layers, and the like. As noted above, ball 600 is intended to be used as a typical conventional golf ball 100 may be used, and its construction largely follows typical or traditional construction methods. The present disclosure is not intended to depart from conventional or traditional manufacturing technologies as indicated at block 901, nor is it intended to re-define or otherwise to modify typical golf ball construction techniques, mechanical processes, or other internal design or materials selection considerations.

A dimple pattern may be created on a surface of the ball (such as ball 600) as indicated at block 902. This operation may be influenced, affected, or otherwise determined by the manner in which conventional manufacturing techniques (block 901) are implemented and relate to or are associated with manufacture of, in the case of block 902, the outer surface or casing of ball 600. Specifically, a dimple pattern may be stamped onto an exterior or outward-facing surface of ball 600, or it may be cast, injection-molded, ground or milled, or otherwise fabricated to create depressions 101 and relatively raised portions 102, or their functional equivalents. As noted above with respect to generic fabrication techniques, the present disclosure is not intended to be limited by the methods or industrial processes used to manufacture dimple patterns on a ball 600 as contemplated by the operations at block 902.

A dimple-free zone (such as dimple-free zone 699) may be created on a surface of the ball (such as ball 600) as indicated at block 903. Such a dimple-free zone 699 may generally be independent of, and distinguished from, any dimple pattern disposed on a surface of ball 600. As with the dimple pattern noted above with reference to block 902, the operation depicted at block 903 may comprise or be embodied in stamping, casting, injection-molding, grounding or milling, or other fabrication techniques sufficient to create a relatively smooth (i.e., non-dimpled) surface independent of and distinct from a dimple pattern otherwise disposed on the surface of ball 600; such techniques are generally known in the art. As noted above, a dimple-free zone 699 may be fabricated at a level (or radial distance from a center of mass of ball 600) that is at or is lower than a depression 101, that is at or is higher than a relatively raised portion 102, or that is somewhere in between. As set forth herein, two requirements may generally influence or affect creation of dimple-free zones 699 as contemplated at block 903: first, a dimple-free zone 699 may generally be free from dimples or other material surface irregularities or deformities that might tend to cause a deviation in trajectory when ball 600 is struck by a putter or other low-speed club stroke that does not cause ball 600 to compress (as described above); and second, a dimple-free zone 699 should be so sized, dimensioned, and configured or oriented (relative to others, for example) on a surface of ball 600 so as not to affect performance of ball 600 in play regimes other than putting or low-speed, low-compression shots.

The operation depicted at block 903 (and the feedback loop represented by decision block 999) may result in creation of a dimple-free zone 699 that is embodied in or comprises a discrete point or a discontinuous region (such as are illustrated in FIGS. 6A an 7A, for instance), that is a continuous band or circumferential swath (such as are illustrated in FIGS. 8A and 8B, for instance), or that comprises a combination of these or other configurations. In that regard, a determination may be made at decision block 999 whether additional dimple-free zones 699 may, should, or must be added in the context of ball fabrication method 900 and in accordance with a preferred or desired fabrication paradigm. In some situations, a configuration or arrangement of dimple-free zones 699 may be implemented symmetrically or equidistantly on a surface of ball 600 such that play characteristics of ball 600 may not be adversely impacted by inclusion or incorporation of one or more dimple-free zones 699 as set forth herein. Accordingly, the decision and operation depicted at blocks 999 and 903 are intended not only to determine whether, but also where and in what manner, an additional dimple-free zone 699 should, or beneficially could, be added to a surface of ball 600.

As noted above, it may be desirable that dimple-free zones (such as dimple-free zone 699) are distributed, disposed, positioned, oriented, or otherwise located or equidistantly or otherwise in a symmetrical manner on, about, or with respect to a surface of ball 600. In practice, this symmetry may satisfy two goals: first, such symmetry is (or may be) a requirement for compliance with USGA or other governing bodies' rules of golf addressing equipment; and second (and equally important), such symmetry typically may have favorable effects in connection with aerodynamic forces that influence drag during flight of a golf ball (such as ball 600).

Upon creation of dimple-free zones 699 (as indicated at blocks 903 and 999), graphic elements (such as described above in connection with reference numerals 610, 620, and 820) may (if desired) be created, provided, or otherwise disposed upon a surface of ball 600 as indicated at block 904. This may be effectuated with inking techniques, silk screening methods, or other types of marking technologies that are generally known in the industry.

It is noted that the arrangement of the blocks and the order of operations depicted in FIG. 9 are not intended to exclude other alternatives or options. For example, the operations depicted at blocks 902 and 903 may be reversed in order, or they may be made to occur substantially simultaneously in some implementations. Further, the operation depicted at block 904 may occur substantially simultaneously with the operation depicted at block 903 in instances where it is desirable to provide nearly instantaneous or real-time printing of graphic elements (610, 620, or 820) in connection with establishing or otherwise providing dimple-free zones 699. Those of skill in the art will appreciate that the foregoing subject matter is susceptible of various design choices that may influence the order or arrangement of the operations depicted in FIG. 9. The present disclosure is not intended to be limited by the example shown in FIG. 9 or the description set forth above.

Several features and aspects of a golf ball and method have been illustrated and described in detail with reference to particular embodiments by way of example only, and not by way of limitation. Those of skill in the art will appreciate that alternative implementations and various modifications to the disclosed embodiments are within the scope and contemplation of the present disclosure. Therefore, it is intended that the present disclosure be considered as limited only by the scope of the appended claims. 

What is claimed is:
 1. A golf ball comprising: a dimple pattern disposed on a surface of the ball; and a first dimple-free zone disposed on the surface, wherein the first dimple-free zone is substantially free of surface irregularities.
 2. The golf ball of claim 1 wherein the first dimple-free zone is circular in shape.
 3. The golf ball of claim 1 wherein the first dimple-free zone is in a shape that is contoured based upon a portion of the dimple pattern that is occupied by the first dimple-free zone.
 4. The golf ball of claim 1 wherein the first dimple-free zone comprises a circumferential band.
 5. The golf ball of claim 1 further comprising: an additional dimple-free zone disposed on the surface, wherein the additional dimple-free zone is substantially free of surface irregularities and positioned opposite the first dimple-free zone on an axis through the ball.
 6. The golf ball of claim 1 further comprising a plurality of additional dimple-free zones, wherein each of the plurality of additional dimple-free zones is substantially free of surface irregularities, and wherein the first dimple-free zone and the plurality of additional dimple-free zones are distributed symmetrically on the surface.
 7. The golf ball of claim 4 further comprising an additional dimple-free zone disposed on the surface, wherein the additional dimple-free zone is substantially free of surface irregularities and comprises an additional circumferential band, and wherein the first dimple-free zone and the additional dimple-free zone are distributed symmetrically on the surface.
 8. The golf ball of claim 4 further comprising a plurality of additional discrete point dimple-free zones disposed on the surface, each of which is substantially free of surface irregularities, and wherein the first dimple-free zone and the plurality of additional discrete point dimple-free zones are distributed symmetrically on the surface.
 9. The golf ball of claim 1 further comprising a graphic element disposed on the surface and comprising a visual indictor of a location or orientation of the dimple-free zone.
 10. The golf ball of claim 4 wherein the dimple-free zone provides a visual cue to align the golf ball for play.
 11. A method of manufacturing a golf ball having dimple-free zones, the method comprising: creating a dimple pattern on a surface of the ball; and creating a dimple-free zone on a surface of the ball independent of the dimple pattern, wherein the dimple-free zone occupies a portion of the surface of the ball in lieu of the dimple pattern and is substantially free of surface irregularities.
 12. The method of claim 11 wherein the creating a dimple-free zone comprises disposing the dimple-free zone on the surface in a circular shape.
 13. The method of claim 11 wherein the creating a dimple-free zone comprises disposing the dimple-free zone on the surface in a shape that is contoured based upon a portion of the dimple pattern that is occupied by the first dimple-free zone.
 14. The method of claim 11 wherein the creating a dimple-free zone comprises disposing the dimple-free zone on the surface in a circumferential band.
 15. The method of claim 11 further comprising: creating a plurality of additional dimple-free zones, each of the plurality of additional dimple-free zones being substantially free of surface irregularities; and distributing the first dimple-free zone and the plurality of additional dimple-free zones symmetrically on the surface. 